Thank you for giving us the chance to provide you servicing. In order to spread your expenses evenly among all sources of income, it is better to create a spreadsheet and divide the expenses as per the income. For instance, if source of income A had 50 expenses and income B had only 20 expenses, it's always better to split them with respect to income. This was you will know which is profitable.
If you enter all the expenses under one income there are higher chances of CRA questioning the expenses.
They will want to assess that why income A have 70 expenses and have income B have 0.
Also check out the link how CRA advises to enter expenses
Hope this clarifies your doubt.
